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Electric (corded) hammer drills

Last week, I did an HVAC job where I had to cut two 10x4 vent holes in the floor of rooms, through 4" of concrete. I do not do this often, however when I do it takes a LONG time (the first one was a little over an hour... the second was almost 2 hours due to rebar).

While I was drilling, the chuck head (SDS style bit) loosed its grease seal and started throwing grease. I did finish the holes... however my gut instinct is this hammer drill is almost history (it is many years old).

Generally, I use the hammer drill to cut holes for condensing furnace flues, ducts, and vents. I have been doing this with lots of 1/2" holes and use the chisel feature to chip out between the holes. I would like to use a hole saw for the PVC furnace vents though. I have lots of SDS bits.

I was in HD today and looked at Makita, Bosch, and Hilti. The Hilti (HD is selling them off, they will not handle that brand anymore) is just too much $$$ for the amount I will use it.

I kinda liked the Makita... yet am not sure if I want the 1" or 1-1/4"... The smaller one is a conventional design... straight drill with D handle at the back. The larger one is the angle design and appears more rugged. Price is $200 and $300... both come with a bonus 4-1/2" grinder.

Does anyone have experience with these Makita hammer drills, are they durable, is the heavier one worth the extra $100, is the angle design a good idea or difficult to use?

Bosch makes very good corded tools. You should look into " Rotary Hammer Core Bits".

You could also look at a smaller Core set up. We had a Shibuya at my old company and it worked very well. You can find them for $1000 on ebay every now and then. They weight very little and are very easy to use and you can just go right through the rebar.

I have a Makita cordless hammer drill for the small stuff, works good, I've used a masterforce (menards store brand) drill worked well lots of power but the chuck wore out after a couple months and would not stay tight only used it on holes less then 1". For cored holes for vents and such I have a Milwaukee rotary hammer 3 and 4 inch core bits no problem and fast to, but core bits really slow down when you hit rebar

I have gone Bosch for all corded and cordless tools. 3 year warranty, even for commercial. I stripped low range out of my 18V Brute Drill with about 40 days left on warranty. I abuse it pushing much larger bits and hole saws than it is designed for. Called, sent it in, they paid freight back, 1 week turnaround. I was impressed!

We have a few bulldogs that we use but I don't know if they would do 4" of concrete.... The guy I ride to work with says the bulldog is as good as any of them.
The Hilti we have is a beast but who can afford that?

We have a few bulldogs that we use but I don't know if they would do 4" of concrete.... The guy I ride to work with says the bulldog is as good as any of them.
The Hilti we have is a beast but who can afford that?

Agree... Hilti are just too much $$$. HD quit carrying them in my area... there were a few discounted ones... still lots of $$$.